High tension circuit interrupter



Feb. 21, 1933. RUPPEL 1,898,901

HIGH TENSION CIRCUIT INTERRUPTER Filed Aug. 27, 1928 2 Sheets-Sheet 1Fig. 4.

Fig.2. Fig.3.

Feb. 21, 1933. s. RUPPEL HIGH TENSION CIRCUIT INTERRUPTER Filed Aug. 27.1928 2 Sheets-Sheet 2 //7 ventor:

Patented Feb. 21, 1933 PATENT OFFICE SIGWART RUPPEL, FFBANKFORT-ON-THE-MAIN, GERMANY HIGH TENSION CIRCUIT INTERRUPTERApplication filed August 27, 1928, Serial No. 302,368, and in GermanyAugust 80, 1927.

My invention relates to high tension circuit interrupter-s of thegas-blast type and has for its principal object the provision of animproved circuit breaker of the aforesaid type capable of quicklyextinguishing high tension power arcs.

In my copending application Serial No. 217,438, filed September 3, 1927,there is disclosed and claimed a method of and apparatus forinterrupting high tension arcs by means of a gas blast directed betweenthe electrodes. The present invention is an improvement thereover and isdirected to auxiliary arcing means for aiding interruption of arcing bythe gas blast.

In accordance with my invention one contact or electrode is providedwith a channel, as a diverging gas passage, and the other electrode isarranged to contact with the firstnamed electrode at the restrictedportion of said passage, said point of contact forming the main currentcarrying area. Auxiliary arcing means coacting with the aforesaidelectrodes are disposed within the diverging passage beyond the maincontact surfaces so that upon separation of the electrodes the gas blastdirected between the same is effective to transfer arcing to theauxiliary arcing means within the diverging passage where it isextinguished.

My invention will be more fully set forth in the following descriptionreferring to the accompanying drawings, and the features of noveltywhich characterize my invention will be pointed out with particularityin the claims annexed to and forming a part of this specification.

Referring to the drawings, Fig. 1 is a fragmentary view, partly insection, of a circuit interrupter of the gas-blast type embodying myinvention; Figs. 2, 3, 4, 5 and 6 are detailed views, partly in section,of different forms of electrodes and arcing means; Figs. 7 and 9 arefragmentary views, partly in sec- 45 tion, of other forms of electrodestructures wherein the main contacts are separately controlled; Fig. 8is a View, partly in sec tion, illustrating electrode structure andoperating means therefor; Fig. 10 is a frag- 50 mentary view, partly insection, of another form of circuit interrupter having main andauxiliary contacts arranged to coact in accordance with my invention,and Fig. 11 is a sectional view showing another form my invention maytake. 5

There is illustrated in Fig. 1 the electrode structure of a gas-blastcircuit breaker comprising movable contact structure 1 and a stationarycontact or electrode 2 forming adiverging exhaust passage, at therestricted portion of which the movable contact or electrade structure 1is normally disposed. In accordance with my invention as set forth in myaforesaid copending application, separation of the contact surfaces isaccompanied by a blast of gas through the diverging passage toextinguish arcing between the electrodes.

I have found that under certain conditions the arc produces acounter-pressure to the gas blast directed between the electrodes,thereby reducing the velocity and extinguishing action of the gas blast.Under certain conditions upon opening movement of the electrode, whereinthe inner or rod-like contact is moved in opposite direction to the gasblast, the arc travels in a direction opposite to that of the gas blastso that the are persists and is not extinguished. This disadvantage isavoided, in accordance with my invention, by transferring the are fromthe restricted portion of the passage to the diverging portion which isprovided with auxiliary arcing means so that the arc is finallyextinguished in the diverging portion. In this arrangement the pressurewaves produced by the arc extend in the direction of the increasingcross section of the diverging passage, that is, in the direction of thegas blast itself, so that a serious counter-pressure is not exerted bythe arc. The counter-pressure of the arc is further minimized by the useof auxiliary arcing portions composed of a metal resistant tovaporization, as tungsten or the like. where the mass of the arc streamand its conducting constituents are reduced to a minimum, interruptionof arcing by the gas blast is greatly facilitated even though theamperage and current density are high.

To this end the rod portion 3 of the movable electrode is provided atits upper end with an auxiliary contact portion 4 arranged to engage inthe closed circuit position the c-oacting auxiliary contact portions 6forming part of the electrode 2. The arrangement 1s such that uponopening or downward movement of the rod 3 the main contact surfaces at 1separate prior to separation of the auxiliary arcing contacts 4 and 6.It shall be understood that this may be accomplished in a number ofdiflerentways, the construction shown being merely an illustration ofthe principle involved. The rod 3 is provided with a lost-motionconnection with the auxiliary arcing contact 4 comprising resilientmeans as a spring 7 arranged to bias upwardly the stem 8, which is inguided and sliding relation to the rod 3, so that the contact 4 isnormally biased into engagement with the coacting arcing portions.

The main contact portions 1 are resiliently secured to the contact rod3, as by laminated springs 9. The springs serve normally to bias thecontact portion 1 into engagement with the inner wall of the nozzle-likeelectrode 2 at the restricted portion thereof.

The operation of the device is as follows: When the rod contact 3 islowered to open the circuit interrupter the contacts 1 will'be drawnaway from the stationary electrode by the springs 9 which normally exerta radial force on the contacts 1. Separation of the contact surfaces at1 therefore efl'ects transfer of the circuit through the arcing meanswithin the diverging exhaust portion. During the initial openingmovement of rod 3 the spring 7 maintains the auxiliary contacts inengagement until the stop member 8 is engaged by the rod 3. Separationof the auxiliary arcing contacts occurs coincident with or subsequent toa blast of gas which is directed into the casing 16 and through thenozzle-like electrode 2. The auxiliary arcing contacts are preferablycomposed of a material, as tungsten or the like, which is resistant tovaporization and produces a minimum amount of metallic vapor in the arcstream.

When thegas blast is directed between the electrodes, the gas flows athigh velocity past the open contact surfaces at 1 into the divergingportion of the exhaust passage to interrupt the arc at the auxiliaryarcing means 4 and 6. By arranging the main contact surfaces at therestricted portion of the passage, flashover or shifting of the arc fromthe auxiliary back to the main contact is substantially precluded, thearc instead being blown further into the diverging portion of thepassage.

In order to produce at the initial opening of the switch a strong gasblast, the main contacts in their closed position may wholly or partlyclose the restricted portion of the passage, the passage being openedupon openmea er ing of the main contacts. During the switching operationthe passage at the main contacts will be traversed by gas with highvelocity and force. Separation of the electrodes may be effected in anysuitable manner, as by well known mechanical operating mechanisms or bypneumatic means generally shown in Fig. 11.

The relation between the arc gap and the source of gas pressure or gasreservoir is preferably such that the gas blast is directed across thearc with mimmum loss of pressure. In other words, it is desirable thatthe gas reservoir be closely positioned with respect to or form a partof the switch chamber itself.

In Fig. 2 there is illustrated movable electrode structure arranged toclose the restricted portion of the passage in the closed circuitposition. In this case flexible bands 10 are disposed between thecontact portions 1 and the auxiliary arcing contact 4 and rod 3,respectively. The control of the contacts 1 by the rod 3 is aspreviously described.

In Fig. 3 a generally similar structure is shown wherein the springs 9are combined with the flexible bands 10, the upper ends being free andonly their lower ends being secured to the rod 3.

In similar structure shown by Fig- 4 the lamlnated springs are replacedby a helical sprlng 9a which is inserted between the auxiliary contact 4and the rod 3, the operation bemg generally as above described.

In place of separate auxiliary contacts, the auxiliary arcing means maycomprise an annular member 12 as illustrated in Figs. 5 and 6. As shown,the annular member 12 is mounted within the diverging part of theexhaust passage and is flared in conformity with the nozzle exhaust. Thearcing portion 4 engages one end of the member 12 in the manner of avalve engaging its seat. As in the previous instance, the gas blast isdi-' rected through the restricted portion of the passage between theelectrodes and extinguishes the are within the diverging portion at theannular member 12. Fig. 6 shows a similar arrangement wherein thecontact 4 is provided with an extension 13. In this case the annularmember 12 and the extension 13 may be wholly or partly composed ofspecial materials as graphite and the like.

Fig. 7 discloses another form of electrode structure wherein the maincontacts 1 are supported by a pair of levers 14 pivotally mounted as at14a on the rod 3. The lower ends of the lever are provided with camfaces arranged to engage cam blocks 15 disposed within the casing 16.Resilient means, as an elliptical spring 17, tends to bias the levers 14apart and into engagement with the blocks 15. Upon opening of the switchthe levers 14 are moved away from the blocks 15 by the downward movementof the central rod 3 so gree of movement of the contacts 1 may beobtained. The contacts 1 may wholly or in part consist of a metal whichis resistant to vaporization for reasons previously set forth. Ifdesired, the nozzle-like electrode 2 may be of the resilient segmentaltype. In this case the nozzle is split into segments as at 2a andsurrounded by an annular compression spring 2b or the like.

U on o ening of the switch an arc is first pro uced hetween the contacts1 and the electrode 2 coincident with the gas blast through the exhaustpassage. Under the influence of the gas blast the arc is transferredfrom the contacts 1 to the auxiliary contact 4 and particularly to thearcing tip 13 of the auxiliary contact. In consequence thereof the arctravels into the widened portion of the exhaust passage and is hereextinguished by the blast. The gas flows at high velocity past thecontacts 1 thereby preventing restriking or fiashover of the arc to themain contacts.

Fig. 8 illustrates another form of electrode structure and operatingmeans therefor comprising a movable rod contact 4 and a stationarynozzle-like contact 2. Mounted within the nozzle portion 2 are contacts33 biased as by springs 34 into engagement with rod contact 4. Suitablemeans 35 are provided for adjusting the tension of the spring 34. Thecontacts 33 are disposed at the restricted portion of the divergingpassage where the gas velocity is high and are provided at their contactsurfaces, or entirely, with a special metal which is resistant tovaporization or chemically inert, as rustless steel, tungsten, nickel,black lead, and the like. In order to minimize breaking up of -the gasflow by the contacts they may be stream lined. If desired, strips orribs 32 may be provided on the contact or arcing surface of the rod 4 tocoact with the contacts 33. The strips 32 may be composed of a metalresistant to vaporization, as above described, and may be stream linedand in connection with the extension 13. i

If it is desired to introduce an extingu shing agent, as carbontetrachloride or the like, a nozzle 36 may be provided below the contact33. Such an agent, which may be in the form of a liquid, gas or powdermay be ad mitted to separately controlled passages, as by an ejector orthe like (not shown), or entrained by the gas flowing through thenozzle.

The pneumatic operating means shown by way of example comprises a piston4' suitably arranged to cause reciprocatory movement of the rod 4. Thepiston is mounted within a cylinder 4 which is connected at one'end to asource of pressure generally indicated at P. Admission of gas to thecylinder causes opening of the switch. The switch casing 16 is likewiseconnected as by a pipe 16 to the source of pressure so that the gasblast may be concurrent with opening movement of the rod contact 4.

Fig. 9 shows a switch generally similar to that shown in Fig. 7. Thelevers 14 to which the main contacts 1 are connected are pivoted on thecentral rod 3 at 146, the inner ends of the levers being connected to arod 18. A spring 17b connected at one end o the arcing portion 4 and atits other end to the inner ends of the levers 14 tends to bias the maincontacts into normal engagement. Upon opening of the switch the rod 18is first moved downwardly, the rod 3 remaining in position. Accordingly,the contacts 1 are rotated out of engagement with the stationaryelectrode 2 producing an are between portions 1 and 2. Under theinfluence of the gas blast the arc at once is transferred to the arcingportion 4 and to the diverging wall of the electrode 2. The are istherefore extinguished within the diverging exhaust. Since the spring 17b is placed under tension by the initial movement of the rod 18 thearcing portion 4 is shortly thereafter moved downwardly also andwithdrawn from the exhaust passage. The arc, however, is extinguished bythe blast before the portion 4 reaches the restricted part of thepassage.

Fig. 10 illustrates another form of auxiliary arcing means. The nozzleelectrode 2 is mounted within a casing 16a which is secured to the topof the insulating switch casing 16. The nozzle 2 is provided with springbuffers 19 and adjusting means 20 therefor arranged so that limitedaxial movement of the nozzle 2 within the casing 16a is permitted. Inthe present case when the pressure of the gas within the casing 16overcomes the pressure of springs 19 the nozzle 2 is moved upwardly andlifted away from the stationary central rod 3 including the arcingportion 4 and the t p extension 13. The auxiliary arcing means 6 formingpart of the nozzle 2 are arranged beyond the restricted portion of thepassage so as to be within the diverging gas flow. Accordingly, the arcis transferred, upon separation of the electrodes at the restrictedportion, to the auxiliary arcing means 613 within the diverging passageand is there extinguished.

It will be understood, of course, that the resilient contact structureillustrated in Fig. 1 may be used in the above arrangement if desired.

There is likewise shown in Fig.-11 electrode structure of the characterabove described arranged for relative movement. A stationary central rod3 formed as a tubular member open at its upper end and a movv thenozzle, with the arc, moves downwardly and the gas blast from thepassages 3a is directed on the are so as to transfer the same from theengaging surface at the restricted portion of the exhaust passage to thetip of. the arcing pin or portion 4 which is carried at the end of rod 3in fixed proximity to the gas exhaust passages 3a. It will, therefore,be apparent that the gas exhaust from the outlets 3a bears a fixed spacerelation to the arcing pin so that a gas stream of substantially uniformvelocity on the engaging surface of the arcing pin is maintained duringthe switch opening operation. Accordingly, in this operat on the are isextinguished within the diverging part of the passage. A particularadvantage of the modification described lies in its simplicity ofdesign. It will be apparent, of course, that relative movement may beobtained as by having the central rod movable upwardly or by movement ofboth electrodes.

It should be understood that my invention is not limited to specificdetails of construction and arrangement thereof herein illustrated, andthat changes and modifications may occur to one skilled in the artwithout departing from the spirit of my invention.

I claim:

1. A high tension circuit interrupter comprising a pair of electrodes,one of said electrodes having a nozzle-like expanding passage withinwhich the other electrode is disposed in the closed circuit position ofthe interrupter, the main contact surfaces of said electrodes coactingadjacent the throat of said passage, arcing means extending within theexhaust expanding portion of said passage, and means for directing gasat high velocity between said electrodes and through said nozzle-likepassage so that the are formed upon separation of said main contactsurfaces is extinguished at said arcing means within said exhaustportion.

2. A high tension circuit interrupter comprising relatively movableelectrodes, one of said electrodes surrounding the other in the closedcircuit position and provided with a diverging exhaust passage,auxiliary arcingmeans extending within said passage, said electrodesengaging in the closed circuit position adjacent the entrance of saidexhaust passage, and means for directing a gas at high velocity betweensaid electrodes'upon separation thereof through said diverging passagefor transferring the are formed upon separation of said electrodes tosaid auxiliary arcing means within said diverging exhaust passa e.

3. K circuit breaker for interru ting high tension power arcs comprisinga uid chamber, an electrode having a nozzle-like passage mounted at oneend of said chamber, said passage communicating at one end with saidchamber and exhausting into a region of low pressure, a coacting rodelectrode mounted within said chamber and engaging said firstnamedelectrode within said passage, the main contact surfaces of saidelectrodes being disposed adjacent the entrance of said passage,auxiliary arcing means comprising part of said rod electrode disposed inthe exhaust port-ion of said passage, and means for directing a gas athigh velocity from said chamber through said passage and between saidelectrodes upon opening movement thereof so that the are formed uponseparation of said electrodes is transferred to said auxiliary means andextinguished-by an expanding jet of high-velocity gas within saidexhaust portion.

4. A high tension circuit interrupter comprising an electrode providedwith a passage defined by a constricted and a diverging exhaust portion,a coacting electrode disposed within said passage in the closed circuitposition of said interrupter, the main contact surfaces of saidelectrodes engaging adjacent said constricted portion, auxiliary arcingcon tacts associated with said electrodes disposed in said divergingexhaust portion, means for effecting separation of said main contactsurfaces prior to separation of said auxiliary contacts, and means fordirecting'a gas at high velocity through said constricted portionbetween said main contact surfaces and through said exhaust portionwhereby the are formed between said auxiliary contacts is interrupted insaid exhaust portion beyond the main contact surfaces.

5. A high tension circuit interrupter comprising a pair of electrodes,one of said electrodes having a nozzle-like passage within which theother electrode is disposed in the closed circuit position of theinterrupter, main current-carrying contacts disposed at the constrictedportion of said passage,-'auxiliary arcing contacts associated with-saidelectrodes disposed within the exhaust portion of said passage, meansincluding a lostmotion connection for effecting opening movement of themain contacts prior to sep aration of the auxiliary contacts, and meansfor directing a gas at high Velocity upon separation of said electrodespast said main contacts and through said exhaust portion forinterrupting therein the are formed at said auxiliary contacts.

ll? said passage, auxiliary contacts carried by each of said electrodesextending into said exhaust portion, means for eflecting electrodeopening movement prior to separation of the auxiliary contacts, andmeans for directing gas from said chamber at high velocity between saidelectrodes and through said exhaust portion to interrupt the are at saidauxiliary contacts.

7. A circuit breaker for interrupting high tension power arcs comprisinga fluid chamber, an electrode having a passage including a constrictedand a diverging exhaust portion mounted at one end of said chamber, saidpassage communicating at one end with said chamber and exhausting into aregion of low pressure, a coacting rod electrode mounted within saidchamber and engaging said first-named electrode adjacent the constrictedportion of said passage, said rod electrode provided with an arcingportion extending within the exhaust portion of said passage, coactingarcing portions mounted within the exhaust passage in the otherelectrode, the main contact surfaces of said electrodes being disposedadjacent said constricted portion, and means for directing a gas at highvelocity from said chamber between said electrodes upon opening movementthereof and through said passage whereby the are formed adjacent saidconstricted portion is transferred to said arcing portions andinterrupted within said exhaust portion.

8. A circuit breaker for interrupting high tension power arcs comprisinga sleeve-like electrode having a passage defined by constricted anddiverging exhaust portions, a fluid chamber in communication with saidpassage at one end thereof, said passage exausting into a region of lowpressure, a coacting rod electrode mounted for reciprocal movementwithin said chamber for engaging said sleeve electrode within saidpassage and adjacent the constricted portion thereof, said rod electrodeprovided with an arcing tip of material resistant to vaporization athigh temperatures extending within the exhaust portion of said passage,the main contact surfaces of said electrodes being disposed adjacent theconstricted portion of said passage, and means for directing a gas fromsaid chamber between said electrodes at a velocity suflicient toovercome the pressure of the are formed between said electrodes wherebysaid are is interrupted at said arcing tip within said exhaust portionin an expanding jet of high velocity gas.

9. A circuit interrupter of the gas-blast type comprising relativelymovable electrodes, one of said electrodes having a diverging exhaustpassage and the other of said electrodes comprising a rod membernormally engaging said first-named electrode adjacent the restrictedportion of said passage, and means directing gas at high velocitybetween said electrodes upon separation thereof and through saidpassage, said rod member including an arcing tip arranged to extendappreciably within said diverging passage in the direction of gas flowafter sep aration of said electrodes.

10. In a gas blast circuit breaker including a pair of relativelymovable contacts between which a gas blast is directed for extinguishingarcing, one of said contacts comprising a nozzlelike structure formingthe exhaust passage of the gas blast, the other coacting contactcomprising a pin engaging and surrounded bv said nozzle contact in theclosed circuit position, and means forming a gas passage from a sourceof pressure to an outlet in fixed proximity to the engaging surface ofsaid coacting contact, so that the exhaust from said outlet impingesdirectly upon said engaging surface during the opening of the circuitbreaker.

11. A gas blast circuit breaker comprising a nozzle contact and acoacting contact comprising a pin engaging and surrounded by said nozzlecontact in the closed circuit position, a tubular member communicatingwith a source of gas pressure and forming a passage for directing gas tothe point of separation of said contacts and through said nozzlecontact, said contact pin carried by and positioned a fixed distancebeyond the open end of said tubular member.

In testimony whereof I aflix my signature.

SIGWART RUPPEL.

